1. Field of the Invention
The present invention deals with types of apparatus which are useful in the applying of materials along highway borders and center islands thereof. It is often desirable to spray materials adjacent such longitudinally extending highway fixtures such as guard rails in order to control the growth of grass, weeds and other vegetation therealong. In order to control this growth, normally a truck will carry a trailer therebehind or may include a tank directly on the truck which functions as a reservoir for holding the supply of material to be applied to the ground adjacent the guard rail.
Normally such vehicles require operation by two men wherein one person drives the truck and the other person directs the spray of material. Normally chemical earth sterlization materials are used to kill all such grass and other weeds adjacent guard rails and the like due to the fact that highway mowing teams cannot mow these grasses and other weeds which are adjacent the longitudinally extending highway fixtures.
2. Description of the Prior Art
Presently one person drives the reservoir vehicle whereas the other person carries a hose which is manually used to apply the chemical earth sterilization liquid in an area at least one foot to both sides of the guard rails or other longitudinally extending highway fixtures. Normally such guard rails are approximately two to three feet above ground level but this dimension may vary six inches in either direction. The present invention provides a means for closely following the top edge of the guard rail and thereby automatically maintaining the proper orientation of the spray nozzle with respect to the ground area.
Prior art devices have been tried but no such device has proved as successful as the apparatus of the present design. In particular the following patents disclose configurations having similar boom structures in comparison to the present invention.
U.S. Pat. No. 978,082 Wallace; PA1 U.S. Pat. No. 1,118,091 Willis et al; PA1 U.S. Pat. No. 2,518,952 Sohmer; PA1 U.S. Pat. No. 3,148,833 Wilson et al; PA1 U.S. Pat. No. 3,395,503 Greenburg et al; PA1 U.S. Pat. No. 3,565,341 Burroughs; PA1 U.S. Pat. No. 3,687,371 Swager.
Of these U.S. Pat. No. 3,687,371 shows a means for spraying curbs in particular for painting wherein a roller number 26 is included for following the upper member of the curb however the design does not include the laterally extendable and retractable boom arm as claimed and disclosed in the present invention. Another configuration in the Greenburg patent, i.e., U.S. Pat. No. 3,395,503 shows a manually adjustable spring-mounted boom construction which is adjustable but is not self-leveling due to the requirement of manual adjustment.
Since none of these devices have proved satisfactory in actual operation the manual system utilizing one man driving the vehicle and another man spraying the material has been adopted by most state highway departments and as such the design of the present invention will provide a means for automating this process.